CFC tracer observations indicate that Prydz Bay in the Indian sector of the Southern Ocean is a region of deep and bottom water formation. Results of a circumpolar ocean circulation model which includes CFC, an age tracer, and numerical floats indicate Prydz Bay as being a convection site which contributes to the reservoir of freshly ventilated waters in the Weddell Sea. In contrast to the newly formed Weddell Sea Bottom Water, captured near bottom, water masses of Prydz Bay origin spread on horizons which pass the ridges confining the Weddell Sea, therefore, contributing directly to the ventilation of the global abyss. ¿ 2001 American Geophysical Union